Diabetic animal models are essential for studies in all of the COBRE projects and are also often required by other diabetes researchers. However, induction and monitoring of diabetes and maintenance of diabetic animals for long durations are associated with a tremendous amount of routine work. The goal of this Core is to provide a centralized service for induction of diabetes, maintenance and use of diabetic animals and to provide support to the diabetes research. In the first phase of COBRE, we have establistied the diabetic animal core and diabetic animal tissue bank. The Core has provided diabetic animals, tissues, data and technical assistance to multiple Pis. The Core has greatly increased the efficiency of diabetic animal research and has reduced the costs to PJIs and other COBRE members for diabetic animal models. As diabetes research expands in Oklahoma, there is a demand to expand this Core service to serve more diabetes researchers in Oklahoma. In the second phase of the COBRE, we will continue and augment these Core services. 1). To induce diabetes by streptozotocin injection in rats or mice or in transgenic or gene knockout mice as required by investigators. 2). To breed and genotype genetic diabetic mice and rats. 3). To monitor diabetes by measuring hyperglycemia and inject insulin when necessary. 4). To collect and record clinical data from diabetic animals, such as body weight and urine volume. 5). To monitor renal function of diabetic animals by measuring albumin and creatinine concentrations in the urine. 6). To provide special diets for diabetic animals upon request by users. 7). To induce retinal neovascularization in the oxygen-induced retinopathy (OIR) model, a commonly used model for proliferative diabetic retinopathy. 8). To perform specialized assays to evaluate diabetic complications. 9). To dissect tissues and coordinate sharing of animal tissues. This Diabetic Animal Core will assist the PJIs in their projects and reduce their routine work in the induction and maintenance of diabetic animals. The coordinated sharing of diabetic animal tissues will also substantially reduce the budget for animal models.